Fracturing operations, or fracking, are used to help stimulate an underground formation. These operations are generally accomplished by exerting fluid pressure on the formation until the formation fractures. A selective fracking operation involves applying pressure to an isolated section of the formation. Once one portion has been tracked, the fracking tool is manipulated to isolate and apply pressure to a different section of the formation. This often involves opening and closing valves using balls that are launched into the tubing by a ball launcher. Examples of ball launchers can be found in U.S. Pat. No. 7,571,773 (West et al.) entitled “Multiple Ball Launch Assemblies and Methods of Launching Multiple Balls into a Wellbore” and U.S. pregrant publication no. 2012/0152525 (McGuire et al.) entitled “Low Profile, High Capacity Ball Injector”.